I'm Audie Cornish. And we begin this hour with the Obama administration's aggressive new move to address climate change. The Environmental Protection Agency is proposing regulations to dramatically reduce greenhouse gas emissions from power plants. The EPA sets targets and leaves states to figure out precisely how to make those reductions. The latest - the largest source of electricity in the U.S. is from coal-fired generators. And as NPR's Jeff Brady reports, that means the coal industry has the most to lose from the new rules.

JEFF BRADY, BYLINE: This plan is the centerpiece of President Obama's climate change policy. It's a huge issue for this administration. So when EPA had Gina McCarthy announce the targets this morning, she sought to connect this global issue to individual Americans.

(SOUNDBITE OF PRESS CONFERENCE)

GINA MCCARTHY: This is not just about disappearing polar bears and melting ice caps. Although, I like polar bears, and I know about melting ice caps. This is about protecting our health, and it is about protecting our homes.

BRADY: The EPA rules set a countrywide target for reducing greenhouse gases by 30 percent of what they were in 2005. The country already has made some progress toward that goal but has a long way to go. McCarthy says states will have a lot of flexibility to decide the best way for them to reach their targets. For example, some may choose to build more renewable forms of energy, like wind and solar. Others may choose to upgrade existing coal plants so they emit less carbon pollution.

Each state will have its own target. Some will be less than the national goal of a 30 percent reduction and others will be more, states that rely heavily on coal won't have to cut the full 30 percent. Despite that, these rules were not welcome in coal country.

TOMBLIN: Based on our initial review of these rules, not a single West Virginia power plant would be in compliance if the rules were in effect today, despite the billions of dollars companies have already spent to modernize their facilities.

BRADY: The coal industry already is well into a campaign to convince consumers that the EPA's proposed rules will raise their utility bills. Hal Quinn is president and CEO of the National Mining Association which represents coal companies.

HAL QUINN: We're talking about putting the American public and American businesses on a tight energy budget, which is going to constrict growth and raise energy prices and make energy less secure, particularly in terms of electricity.

BRADY: Quinn also says these rules may ultimately have little effect on global climate change. That's because the rules apply to only to the U.S., which is the second-largest source of man-made carbon dioxide. China is the first. But environmentalists say these rules are about more than the effect they alone will have on climate change. David Doniger directs the climate and clean air program at the National Resources Defense Council. He says these rules put the U.S. in a leadership position.

DAVID DONIGER: Every other big contributor, from China to Europe, is ready to do things. But each one wants to know that the others are in the game. So this is the way the U.S. shows that we're in the game. We're doing our share.

BRADY: It will take some time before the new rules are put into effect, though. The EPA will hold a series of meetings around the country and accept public comments on the proposed rules for the next four months. States will have until June 2016 to come up with their own plans to meet the federally set targets for greenhouse gas reductions. And looming in the background is the threat of lawsuits from opponents that could delay implementation for years. Jeff Brady, NPR News. Transcript provided by NPR, Copyright NPR.